UNI-T UT353 - User Manual

PIN: 110401107881 X
UT353
Mini Sound Meters
Operating Instruction
1.1ntroduction
UT353 is a stable, safe, reliable mini sound meter, widely
used
in noise detection, quality control, health control,
environmental noise measurement in factory, traffic, home
audio and other places.
This operating manual includes relevant safety information
and warnings.
Please read this manual carefully and
observe
all cautions.
.&. Warning:
Before using the product, please read the operation
rules
carefully.
2.0ut of the Box
Open the packing box and take out the meter.
Please check carefylly if any items are missing or
damaged.
1 Wind-proof
ball---------------1
2. Operating manual-----------1
3.0peration Safety
This product strictly follows the requirements of "General
specification for sound level meters" in design and
production.
1.Please check the meter and the accessories before
using and beware of any damage or abnormal
phenomenon. If you find the case is damaged or the
LCD shows nothing, or you consider that the meter could
not work properly anymore, please stop using it.
2.0bserve the operating instructions while measuring.
3.00 not open the meter at will or change internal wiring
to avoid damages to the mater.
4When the LCD displays "COil", replace the battery timely.
Remove the battery if the meter is not used for a
long
time.
5.00 not store or use the meter in high temperature, high
humidity, flammable. combustible or strong electromagnetic
environment.
6.Please use soft cloth and neutral detergent to clean the
case for maintenance. Do not use grinding agent and
solvent
to avoid case corrosion and damage to the meter.
4.Product Outlook
1
Wind-proof
ball
I 2 I
Microphone
3 Meter case
I 4 I
LCD display
5
Function keys
UNI-T.
Wind
(}1
~i)
Figure 1
5. Display Interface
CD
®
HOLD
111111'1
®
J.O.O.O::
®
®
®
FAST SLOW
(j)
Figure 2
1
Maximum measurement
5
A weighted
2
Minimum measurement
6
C weighted
3 Data hold 7
Slow response rate
4
Low battery
8
Fast response rate
9 Measurement value
6. Key Function and Setup
1. ON/OFF:
Short press once to start up; short press again to power
off.
Note:
Product's auto power off feature can be disabled:
Press and hold "HOLD" and then piess "ON/OFF" key to
enable/disable auto power off, LCD will display "APO OFF'
to indicate status.
2. FAST/SLOW:
Sampling
time: When measuring, pressing this key to
select between fast time of 125ms and slow time of 1 s.
3. MAX/MIN:
Pressing
this key to select maximum, minimum and
normal
value measurement; when maximum or minimum
measurement
is selected, the meter always shows the
maximum reading or the minimum reading.
4. HOLD/BL:
HOLD: Short press this key once to hold the
measurement: short press the key once again to exit
data
hold and continue normal measurement.
BL: long press this key to turn on backlight, and long
press it again to turn off backlight.

Summary

Key Function and Setup

ON;OFF

Controls device power on and off.

FAST;SLOW

Selects sampling time between fast (125ms) and slow (1s).

MAX;MIN

Selects maximum or minimum measurement display mode.

HOLD;BL

Holds measurement data and controls backlight function.

Technical Specifications

Noise (dB)

Details sound level measurement range, resolution, accuracy, and rate response.

General Type

Describes the meter's LCD display, overload, and low battery indications.

Environment Specification

Lists operating temperature, humidity, and altitude limits.

Electrical Specifications

Details accuracy, calibration period, and temperature coefficient.

General Maintenance

Provides guidance on cleaning and maintenance procedures.

Battery Installation and Replacement

Instructions for installing and replacing AAA batteries.

Overview

1. Function Description
2. Important Technical Specifications
3. Usage Features
4. Maintenance Features

The UNI-T UT353 Mini Sound Meter is a stable, safe, and reliable device designed for noise detection, quality control, health control, and environmental noise measurement in various settings such as factories, traffic, homes, and audio environments. It adheres to the "General specification for sound level meters" in its design and production.

Function Description

The UT353 measures sound levels within a range of 30 to 130 dB with a resolution of 0.1 dB and an accuracy of ±1.5 dB. It offers two sampling time options: "FAST" at 125ms and "SLOW" at 1000ms, selectable via the FAST/SLOW key. The device can display maximum, minimum, and normal measurement values, toggled by the MAX/MIN key. A data hold function, activated by a short press of the HOLD/BL key, allows users to freeze the current measurement on the display. The HOLD/BL key also controls the backlight with a long press. The meter features an auto power-off function after 5 minutes of inactivity, which can be disabled by pressing and holding "HOLD" and then pressing the ON/OFF key. It provides both A-weighted (dBA) and C-weighted (dBC) measurements, with A-weighting being suitable for general noise measurement and C-weighting for measuring the sound pressure level of mechanical noise.

Important Technical Specifications

Noise (dB):

• Sound Level Range: 30~130dB
• Resolution: 0.1 dB
• Accuracy: ±1.5 dB
• Rate Response: 31.5Hz~8KHz

Sampling Time:

• FAST: 125ms
• SLOW: 1000ms

Display:

• 4-bit LCD display with a maximum display of 9999.
• Overload Indication: "UN" for under range, "OL" for over range.
• Low Battery Indication: Prompt " 1" when power is 3.0~3.5V.

Sensor:

• 1/2 inch condenser microphone

Impact Strength:

• Can withstand the impact of landing from 1 meter height.

Power Requirement:

• 3 pieces of AAA 1.5V batteries.

Product Size:

• 150mm × 52mm × 27mm

Weight:

• 116g

Environmental Specifications:

• Indoor Use: Yes
• Altitude Height: 2000m
• Safety: EN61326-1
• Pollution Level: 2
• Working Temperature and Humidity:
  • 0℃~30℃ (not greater than 80%RH)
  • 30℃~40℃ (not greater than 80%RH)
  • 40℃~50℃ (not greater than 45%RH)
• Storage Temperature and Humidity:
  • -20℃~60℃ (not greater than 80%RH)

Electrical Specifications:

• Accuracy: ±1.5dB (@1kHz Standard audio source).
• Calibration Period: 1 year.
• Environment Temperature: 23°C ± 5°C
• Environment Humidity: ≤80%RH
• Temperature Coefficient: 0.1 × (Accuracy)/°C

Usage Features

The device is straightforward to operate with dedicated keys for its main functions:

• ON/OFF: Short press to power on or off.
• FAST/SLOW: Toggles between fast (125ms) and slow (1s) sampling rates.
• MAX/MIN: Selects between maximum, minimum, or normal value measurement. When MAX or MIN is selected, the meter continuously displays the highest or lowest reading recorded.
• HOLD/BL: Short press to hold the current measurement; short press again to exit data hold. Long press to turn the backlight on or off.

The UT353 comes with a wind-proof ball (foam windscreen) to minimize wind noise interference during measurements. The display interface clearly shows the measurement value, MAX/MIN status, HOLD status, battery indicator, and selected weighting (dBA/dBC) and response rate (FAST/SLOW).

Maintenance Features

• Battery Replacement: The device uses three AAA 1.5V batteries. When the low battery indicator " 1" appears, the batteries should be replaced. The battery cover is located on the back panel and slides open in the direction of the arrow. Users should install new batteries according to polarity indications and use batteries of the same type.
• Cleaning: The case should be cleaned periodically with a soft cloth and neutral detergent. Abrasive or solvent-based cleaning agents should not be used to prevent corrosion or damage to the meter.
• Storage: Avoid storing or using the meter in high-temperature, high-humidity, flammable, combustible, or strong electromagnetic environments. If the meter is not used for a long time, the batteries should be removed.
• Safety Precautions: Users are warned not to open the meter case or change internal wiring to avoid affecting accuracy or damaging the device. Maintenance and service should only be performed by professional personnel or a designated maintenance department. Before use, users should inspect the meter and accessories for any damage or abnormal phenomena. If the case is damaged, the LCD shows nothing, or the meter is suspected to be malfunctioning, its use should be discontinued.

UNI-T UT353 Specifications